1. Field of the Invention
The present invention relates to a method for acquiring vibration data from rotating machines by using a portable vibration measuring device. The invention also relates to such a portable vibration measuring device.
2. Description of Related Art
The condition of rotating machines, for example, in the paper manufacturing industry, may be monitored by regularly performing vibration measurements at specific measuring points by using a portable vibration measuring device having a vibration sensor and a data memory. In order to perform a vibration measurement at a specific measuring point, the user connects the vibration sensor to the measuring point, followed by identification of the measuring point, which can be done manually by the user by entering corresponding information into the measuring device or automatically by the vibration measuring device, if the measuring points each carry a mark which can be read by the vibration measuring device. Subsequently the vibration measurement is carried out by the measuring device and the acquired vibration data is stored in the memory of the measuring device. This procedure is repeated until all prescribed measuring points of the machine have been measured.
Often the manufacturing facility comprises not only a single machine but a plurality of rotating machines which all may be of the same type or which may be of different types. In such cases the user, after having terminated the measurements at the first machine, will continue with corresponding measurements at the other machines until all machines have been measured. Usually the measurements will be conducted according to a predetermined sequence which is also called a “route”. At the end of the route the measuring device will be connected to an external database and the vibration data acquired from the measurements will be uploaded into the database for evaluation.
An example of such a portable vibration measuring device is described in EP 0 999 433 A2, which device comprises a display for presenting information to the user regarding the location of the machines to be measured and regarding the location of the measuring point at each of the machines. The measuring device is capable of automatically identifying the respective measuring point. According to the selected and identified measuring point the vibration measuring device runs a specific measuring procedure. The vibration measuring device provides the user with instructions and information via the display in order to guide the user through the entire measuring route including all machines. To this end, the memory of the measuring device stores corresponding data/information for each machine in a specific manner so that the corresponding measuring prescriptions, etc., are stored in such a manner that they are attributed to each machine specifically; i.e. they are attributed to the name of each machine (the individual machines of the same type are distinguished by specific names).
A similar portable vibration measuring device is described in U.S. Pat. No. 4,612,620, which device has stored therein the entire route, i.e. the scheduled sequence of measuring points at various machines, including measuring prescriptions attributed specifically to each individual machine.
A further similar portable vibration measuring device is described in U.S. Pat. No. 4,520,674, wherein prior to starting the vibration measurements the vibration measuring device is connected to an external database from which information regarding which measurements are to be made, upon which machines the measurements are to be made, how the vibration data should be collected, etc., is uploaded into the memory of the device, with the corresponding information being attributed specifically to the individual machines.
Further portable vibration measuring devices are known from US 2005/0060123 A1 and U.S. Pat. No. 5,808,903, wherein the measuring device includes a database with information attributed specifically to the individual machines to be measured.
U.S. Pat. No. 4,800,512 relates to a portable vibration measuring device which is capable of identifying the respective measuring points carrying a mark.
EP 0 998 661 B1 relates to a portable vibration measuring device for measuring measuring points designed as studs which include a writeable memory. Once the vibration measuring device has been connected to an individual measuring point data from the measuring point memory is uploaded into the memory of the vibration measuring device in order to identify the measuring point and to conduct the vibration measurement in the prescribed manner, whereas at the end of the measurement the acquired vibration data is written into the measuring point memory.
It is an object of the invention to provide for a method for acquiring vibration data from a plurality of rotating machines by using a portable vibration measuring device, which method should be particularly flexible but nevertheless simple to be carried out by a user.
It is a further object of the invention to provide for a portable vibration measuring device which can be used in such a method for acquiring vibration data.